When news broke during the NFL combine that former Utah defensive lineman Star Lotulelei would not be participating due to an undiagnosed heart condition, scouts and fans began to speculate how the condition might affect his NFL career.

Lotulelei, who was projected to be a top pick in this year's NFL draft, was diagnosed with an abnormally low ejection fraction while undergoing routine medical testing before the combine.

What is an ejection fraction?

Ejection fraction is a measure of the amount of blood pumped out of the left or right ventricle of the heart. According to the American Heart Association, a normal heart will pump between 55 to 70 percent of the blood out of the left ventricle of the heart and into the body.

Lotulelei's left ventricle was found to be pumping at only 44 percent — below normal but not considered in the range of heart failure.

Lotulelei's condition could be the result of a suddent drop in heart function caused by something as simple as a viral illness or hormone abnormalities that put undue stress on the heart, according to USA Today, or it could be the sign of a more serious long-term problem such as heart disease or cardiomyopathy.

Lotulelei's condition may be the result of him losing 10 pounds in three days leading up to the combine, USA Today reported.

It must be noted that Lotulelei did not fail his physical, but was rather given an incomplete designation, and asked by combine officials not to participate out of caution. He flew back to Salt Lake City to see a specialist, but was still cleared to exercise.

This is not the first time a draft prospect has been diagnosed with a heart condition before the NFL combine. In 2012, Oklahoma defensive lineman Frank Alexander missed the combine after being diagnosed with a heart condition, but was eventually drafted by the Carolina Panthers after being medically cleared to play.

If Lotulelei's condition is not serious, he should be able to compete at a high level. However, health concerns could cause his draft stock to fall considerably. Lotulelei is expected to fully participate in Utah's pro day March 20.